Solid-lubricant bearing

Abstract

A bearing unit has rolling elements separated by floating solid-lubricant spacers which interfit with the roller elements. When the rolling elements are rollers, the ends of the rollers are lubricated by solid lubricant caps on the rollers, or by end portions of the spacer which overlap the roller ends, or by end ring members of solid-lubricant material. If the bearing unit includes a cage, floating solid-lubricant spacers are located between the cage dividers and the rolling elements.

We claim: 
     
       1. A bearing assembly comprising: a plurality of rollers arranged to roll on a path; and   a plurality of floating spacers between said rollers and concave shaped on opposite sides to interfit with the rollers and travel therewith on said path, said spacers being longer than said rollers and having a solid-lubricant composition.   
     
     
       2. A bearing assembly according to claim 1 in which said rollers and spacers are arranged in a circular configuration. 
     
     
       3. A bearing assembly according to claims 1 in which said rollers and spacers are arranged in an endless noncircular configuration. 
     
     
       4. A bearing assembly according to claim 1 in which said spacers and rollers float together. 
     
     
       5. A bearing assembly according to claim 1 in which said rollers track between inner and outer races and are confined at their ends by said spacers. 
     
     
       6. In a bearing assembly: a spacer having a concave depression closed at opposite ends, said spacer having a solid-lubricant composition; and   a roller having less than half of its circumference fitting into said depression, whereby the circumference and ends of the roll are lubricated by said spacer when the roller turns relative to the spacer.   
     
     
       7. A bearing assembly according to claim 6 in which said roller comprises a plurality of roller elements arranged end to end. 
     
     
       8. A bearing assembly according to claim 6 in which said roller comprises a plurality of roller elements arranged end to end. 
     
     
       9. A bearing assembly according to claim 6 in which said roller comprises a plurality of roller elements arranged end to end, and in which said spacer comprises a plurality of spacer elements arranged end to end. 
     
     
       10. In a bearing assembly: two adjacent spacers having opposed concave depressions, each closed at opposite ends, said spacers having a solid-lubricant composition; and   a roller fitting into said depressions and having part of its circumference exposed, whereby the circumference and ends of the rollers are lubricated by said spacers when the roller turns relative to the spacers.   
     
     
       11. A bearing comprising: inner and outer members providing opposed inner and outer raceways;   rolling elements between said raceways;   spacers located between said raceways and separating said rolling elements, said spacers being free of interconnection with one another and having a solid-lubricant material for lubricating the rolling elements; and   end lubricating means provided by said spacers for end lubricating the rollers by a transfer film of solid lubricant.   
     
     
       12. A self-lubricating bearing comprising a raceway; a plurality of spaced rollers tracking on said raceway, and a plurality of elongated spacers separating said rollers and confining them against movement endwise of the spacers, said spacers having a solid-lubricant composition.   
     
     
       13. A bearing assembly comprising: a plurality of round ceramic roller units arranged to roll on a path provided by a metal race; and   a plurality of spacer units alternating with said roller units and concave shaped on opposite sides to interfit with the roller units through an arc along said path and travel therewith along said path, said spacer units having a polyimide matrix containing a solid-lubricant material.   
     
     
       14. A self-lubricated bearing comprising: an inner race;   an outer race surrounding the inner race;   rollers between said races;   solid-lubricant spacers floating between said rollers and races, said rollers loosely interfitting with said spacers for holding them in position to lubricate the rollers by lubricant transfer from said spacers, the thermal expansion characteristic of the spacers and races being greater than that of the rollers, and the collective thermal expansion of the spacers approximating that of the races so that the interfit of the spacers and rollers remains approximately constant with changes in operating temperatures.   
     
     
       15. A self-lubricated bearing according to claim 14 in which said rollers are ceramic, said races are metal, and said spacers have a polyimide matrix containing solid-lubricant material. 
     
     
       16. A self-lubricated bearing according to claim 14 in which some of said spacers have a higher coefficient of thermal expansion than do others of said spacers. 
     
     
       17. A self-lubricated bearing according to claim 14 in which some of said spacers have a higher coefficient of thermal expansion than do said races, and in which other of said spacers have a lower coefficient of thermal expansion than do said races. 
     
     
       18. A bearing assembly comprising a plurality of elongated rollers each having a longitudinal center axis and arranged to roll on a path; and a plurality of elongated floating spacers between said rollers and concave shaped to interfit with said rollers and travel therewith on said path, said spacers having a solid-lubricant composition and having each of their outer edges recessed from the respective line of contact with the adjoining roller in a longitudinal plane, which forms a dihedral angle of approximately thirty degrees with a longitudinal plane which passes through the center axis of said adjoining roller and is centered relative to the respective ones of said spacers contacting such adjoining roller.